Synergistic electronic regulation and piezocatalytic effect in CoTiO3-BaTiO3 heterojunction for boosting fenton-like oxidation toward pollutants degradation

Water flow is a sustainable mechanical energy source. Utilizing such energy for promoting Fenton-like oxidation toward water remediation is anticipated, yet rarely reported. Herein, CoTiO3-BaTiO3 (CT-BT) nanorod was constructed as piezocatalysis for triggering Fenton-like oxidation toward pollutant degradation via peroxymonosulfate (PMS) activation. The CT-BT was synthesized by coprecipitation method, and its physicochemical property was comparatively analyzed by a series of characterizations, including SEM, TEM, XRD, PFM, FT-IR, N-2 adsorption/desorption, and XPS. The p-n heterojunction formed by CT-BT provided a built-in electric field induced charge redistribution, thereby enhancing affinity toward PMS and facilitating electron transfer. Furthermore, a rectangular tubular reactor was designed to utilize water flow to trigger piezoelectric effect of CT-BT, boosting the generation of reactive oxygen species. High-speed turbulence (turbulent kinetic energy > 50 m(2)/s(2)) was generated as the water flowed through the slits inside the tubular reactor. The water flow greatly promoted PMS activation on CT-BT for berberine degradation (100 % removal within 30 min), with a kinetic constant of 0.1206 min(-1), which was 4.7 times that of the non-piezoelectric catalytic process. Practical application experiments demonstrated decent anti-interference capability and stability (Co leaching < 20 mu g/L) of the piezocatalytic system. This work is hoped to advance piezocatalysis in promoting Fenton-like oxidation through utilizing hydrokinetic energy.